Sending bull to feed test

Have a very nice bull calf we are thinking of sending off to a feed test this fall. Many of his dams herdmates have preformed pretty well there in the past so I am not worried about his performance abilities. I wonder how much this will help with his marketability? When you guys shop for a new herd bull how much emphasis do you put in that kind of performance data? I know feed tests aren't as popular as they once were but I just want some thoughts.